Abstract: An optical system includes a scanning unit, a first lens-element group including at least a first lens element, and a focusing unit which is designed to focus beams onto a focus, wherein the focusing unit includes a second lens-element group including at least a second lens element and an imaging lens. The imaging lens further includes a pupil plane and a wavefront manipulator. The wavefront manipulator is arranged in the pupil plane of the imaging lens or in a plane that is conjugate to the pupil plane, or the scanning unit of the optical system is arranged in a plane that is conjugate to the pupil plane and the wavefront manipulator is arranged upstream of the scanning unit in the light direction. The focus of the second lens-element group lies in the pupil plane of the imaging lens in all focal positions of the focusing unit.

Abstract: The inventions concerns an optical system comprising a scanning unit, a first lens-element group comprising at least a first lens element, a focusing unit which is designed to focus beams onto a focus, wherein the focusing unit comprises a second lens-element group comprising at least a second lens element and an imaging lens. The imaging lens further comprises a pupil plane and a wavefront manipulator. The wavefront manipulator of the optical system is arranged in the pupil plane of the imaging lens or in a plane that is conjugate to the pupil plane of the imaging lens, or the scanning unit of the optical system is arranged in a plane that is conjugate to the pupil plane of the imaging lens and the wavefront manipulator is arranged upstream of the scanning unit in the light direction. The focus of the second lens-element group lies in the pupil plane of the imaging lens in all focal positions of the focusing unit.

Abstract: A method includes generating, using a data processor, information showing variations of a parameter across a photo mask relative to an average value of the parameter measured at various locations on the photo mask. For example, the information can include data points, and each data point can be determined based on a ratio between a measurement value and an average of a plurality of measurement values.

Abstract: A photo mask having a first set of patterns and a second set of patterns is provided in which the first set of patterns correspond to a circuit pattern to be fabricated on a wafer, and the second set of patterns have dimensions such that the second set of patterns do not contribute to the circuit pattern that is produced using a lithography process based on the first set of patterns under a first exposure condition. The critical dimension distribution of the photo mask is determined based on the second set of patterns that do not contribute to the circuit pattern produced using the lithography process based on the first set of patterns under the first exposure condition.

Abstract: Apparatus and method for transmittance mapping of an object which is at least partially transparent to deep ultraviolet radiation. The method comprises directing a wide-band deep ultraviolet radiation so as to illuminate different areas of an array of successive areas of the object; using an optical detector positioned on an opposite side of the object with respect to the radiation source detecting the wide-band deep ultraviolet radiation that emerges from the object; and processing signals from the optical detector to determine the transmittance of the radiation through the different areas of the array of successive areas of the object.

Abstract: A photo mask having a first set of patterns and a second set of patterns is provided in which the first set of patterns correspond to a circuit pattern to be fabricated on a wafer, and the second set of patterns have dimensions such that the second set of patterns do not contribute to the circuit pattern that is produced using a lithography process based on the first set of patterns under a first exposure condition. The critical dimension distribution of the photo mask is determined based on the second set of patterns that do not contribute to the circuit pattern produced using the lithography process based on the first set of patterns under the first exposure condition.

Abstract: In general, in one aspect, a method includes determining a critical dimension (CD) distribution on a photomask by measuring deep Ultra-Violet (DUV) transmission across the photomask.

Abstract: A method includes generating, using a data processor, information showing variations of a parameter across a photo mask relative to an average value of the parameter measured at various locations on the photo mask. For example, the information can include data points, and each data point can be determined based on a ratio between a measurement value and an average of a plurality of measurement values.

Abstract: In general, in one aspect, a method includes determining a critical dimension (CD) distribution on a photomask by measuring deep Ultra-Violet (DUV) transmission across the photomask.

Abstract: Apparatus and method for transmittance mapping of an object which is at least partially transparent to deep ultraviolet radiation. The method comprises directing a wide-band deep ultraviolet radiation so as to illuminate different areas of an array of successive areas of the object; using an optical detector positioned on an opposite side of the object with respect to the radiation source detecting the wide-band deep ultraviolet radiation that emerges from the object; and processing signals from the optical detector to determine the transmittance of the radiation through the different areas of the array of successive areas of the object.